It was a dream scenario for the Colorado Rockies on Sunday as they not only broke their losing streak to improve their record to 2-7, but saw their offense explode for 12 runs against the Athletics in the series finale. ​What was the topping on the sundae was the fact that top pitching prospect Chase Dollander made a strong start in his major league debut, earning his first big league win as the Rockies took down the Athletics 12-5.

Manager Bud Black first shared the breaking news that Dollander would be called up to make a start on Sunday during his media availability last Friday. With Austin Gomber sidelined with shoulder soreness, the team had begun the season with a four-man rotation. The need for a fifth starter finally arose and the team decided to call up Dollander from Triple-A Albuquerque and subsequently optioned Bradley Blalock.

In front of a buzzing crowd eager to see the ninth overall pick of the 2023 MLB Draft, Dollander fired a 97.4 mph fastball to the inside corner of the plate. Lawrence Butler wasted no time swinging against the rookie and lofted a shallow fly ball to left field. It would have easily been a double had left fielder Mickey Moniak not made a stellar sliding catch to get the out.

“I felt everything was working pretty good today — changeup, slider and curveball were all pretty good,” said Dollander, whose four-seam fastball averaged 97.8 mph and topped at 99.3. “I made a couple mistakes and they took advantage. Other than that, I felt good.”

The A’s struck first in the opening inning when Tyler Soderstrom launched a two-run homer off Dollander, giving Oakland an early 2-0 lead. Despite the early setback, Dollander settled into a rhythm as he continued to attack hitters and pound the zone. Of the 79 pitches he threw, 49 went for strikes. It was the type of aggressive pitching that made Dollander so enticing to the Rockies when they drafted him. It was evidence of his ability to pitch without fear.

In the fourth inning he ran into a little bit of trouble he issued three straight singles to start the frame. However, on the single by Miguel Andujar that scored a run, the Rockies were able to get an out at third when Nick Martini threw out Jacob Wilson. Butler would tack on the fourth run against Dollander with a solo home run to start the fifth inning but he quickly bounced back to get the next three batters.

Dollander’s final line for his debut was five innings pitched, allowing four runs on seven hits while striking out six and allowing just one walk. It wasn’t the prettiest of debuts, but considering it was at Coors Field, he’s never pitched at altitude, and he only had one pro season in the minors, it was a stellar debut that hopefully lays the foundation for a strong season for the young right-hander.

​What also helped was that the Rockies offense finally broke out.

After a less-than-stellar first of games, the Rockies offense was off to an ice-cold start. They had only scored more than three runs in a game just a couple of times while strikeouts reigned supreme. While they would strike out 11 times in the game, they made up for it with 14 hits, including six extra-base hits.

In the bottom of the first, the Rockies responded promptly when leadoff hitter Brenton Doyle ignited the offense with a solo home run, his first of the year, cutting the deficit to 2-1.​ Ezequiel Tovar followed up with a single and stole second, eventually coming around to score on a single by Kris Bryant to tie the game 2-2.

In the second inning, Colorado continued to apply pressure. Doyle delivered a two-run double, driving in two runs and putting the Rockies ahead 4-2. Tovar then drove in Doyle with an RBI double to put the Rockies up 5-2. Bryant continued things in the third inning with a leadoff double, coming around to score on a sacrifice fly by Tyler Freeman to put the Rockies up 6-2.

Tovar hit his second double of the game in the fourth inning, coming around to score on an RBI single by Ryan McMahon to make it a 7-3 lead for the Rockies. They would add five more runs in the eighth courtesy of RBI singles from Doyle, Tovar and Hunter Goodman.

The Rockies’ bullpen, which had struggled in recent games, delivered a solid performance. Jake Bird was particularly effective, striking out five of the six batters he faced over two innings. Luis Peralta and Victor Vodnik combined to close out the game, with Vodnik securing his first save of the season.

On the day, Tovar matched his career-high with four hits and drove in three runs while Doyle went 3-for-5 with four RBI. Bryant’s 2-for-5 performance was a welcome sight while Michael Toglia delivered a double for his lone hit of the day. The team went 7-for-13 with runners in scoring position.

On the Athletics’ side, Lawrence Butler had a notable performance, going 2-for-5 with a run scored while Soderstrom’s early home run highlighted a 2-for-3 afternoon.

With this win, the Rockies improved their record to 2-7, aiming to build momentum as they continue their homestand. The A’s, now at 4-6, will look to rebound in their upcoming games. The Rockies are off on Monday and begin a new series on Tuesday when they welcome the Milwaukee Brewers to Coors Field.